Foster optimal balance and mobility and reduce injurious falls among older Americans. Our goals for this five year renewal award are to i. Promote multidisciplinary basic, translational and clinical inquiry into the causes, consequences and treatment of age related changes in balance and mobility, 2. Train young investigators from multiple disciplines within a vibrant intellectual and collaborative environment and 3) Serve as a resource and part:ner to other OAICs, investigators, institutions and the public. Our theme has evolved from a focus on balance and aging to one that better incorporates contemporary perspectives about the interface between balance and mobility, especially the role of control of motion during weight bearing activity. The OAIC has three Resource Cores (RCi- Clinical and Population Research Core, RC2- Tech Core and RC3- Data Management and Analysis Core) an RCDC, a PESC and an LAC. We propose four pilot studies and three developmental projects that reflect the scope and collaborative spirit of our program. The program integrates over 50 externally funded projects, funds three Pepper Scholars and provides support and training to over 20 additional young investigators who are funded through other sources of institutional and individual career awards.